added basic download icon to the window frame

src/widgets/dialogs/UpdatePromptDialog.cpp

@@ -0,0 +1,30 @@
+#include "UpdatePromptDialog.hpp"
+
+#include "util/LayoutCreator.hpp"
+#include "widgets/Label.hpp"
+
+#include <QDialogButtonBox>
+#include <QPushButton>
+#include <QVBoxLayout>
+
+namespace chatterino {
+
+UpdatePromptDialog::UpdatePromptDialog()
+    : BaseWindow(nullptr, BaseWindow::Flags(BaseWindow::Frameless | BaseWindow::TopMost |
+                                            BaseWindow::EnableCustomFrame))
+{
+    auto layout = LayoutCreator<UpdatePromptDialog>(this).setLayoutType<QVBoxLayout>();
+
+    layout.emplace<Label>("An update is available!");
+    layout.emplace<Label>("Do you want to download and install it?");
+    layout.emplace<Label>("This doesn't work yet!");
+
+    auto buttons = layout.emplace<QDialogButtonBox>();
+    auto install = buttons->addButton("Install", QDialogButtonBox::AcceptRole);
+    auto dismiss = buttons->addButton("Dismiss", QDialogButtonBox::RejectRole);
+
+    QObject::connect(install, &QPushButton::clicked, this, [this] { this->close(); });
+    QObject::connect(dismiss, &QPushButton::clicked, this, [this] { this->close(); });
+}
+
+}  // namespace chatterino

src/widgets/dialogs/UpdatePromptDialog.hpp

@@ -0,0 +1,19 @@
+#pragma once
+
+#include "widgets/BaseWindow.hpp"
+#include "widgets/Label.hpp"
+
+namespace chatterino {
+
+class UpdatePromptDialog : public BaseWindow
+{
+public:
+    UpdatePromptDialog();
+
+private:
+    struct {
+        Label *label;
+    } ui_;
+};
+
+}  // namespace chatterino